package com.pet.order.utils;

import lombok.RequiredArgsConstructor;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
@RequiredArgsConstructor
public class RedisIdWorker {
    // 开始时间戳 2024-02-29 9:30:00
    private static final long BEGIN_TIMESTAMP = 1709170200L;
    // 序列号的位数
    private static final int COUNT_BITS = 32;
    private final StringRedisTemplate stringRedisTemplate;

    public long nextId(String keyPrefix) {
        // 1. 生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timestamp = nowSecond - BEGIN_TIMESTAMP;
        // 2. 生成序列号
        // 2.1. 获取当前日期, 精确到日期
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        // 2.2. 自增长
        long count = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + date);
        // 3. 拼接并返回
        return timestamp << COUNT_BITS | count;
    }
}